Performance Engineer Sr

Dayforce

27d•$80,500 - $143,800•Remote

About The Position

We are seeking a Senior Performance Engineer with a strong software engineering background and deep expertise in profiling, debugging, and optimizing application performance at scale. This is a developer-first role focused on improving system efficiency through code-level analysis, architectural insights, and data-driven optimization. You will work closely with engineering teams to identify performance bottlenecks, optimize execution paths, and ensure our platforms are highly scalable, reliable, and cost-efficient. Citizenship Requirement for US Candidates • Must be a US citizen, permanent resident, green card holder of naturalized citizen. • Ability to obtain US security clearance. Note: This position is contingent upon the successful completion of a background clearance in order to operate within the target environment.

Requirements

Strong background in software development with a focus on performance optimization
Proficiency in one or more programming languages: C# and Python
Strong experience with: ASP.NET / .NET application performance tuning and diagnostics
Experience with scripting and automation: Python, JavaScript
Deep hands-on experience with profiling and debugging tools, such as: SQL Profiler, dotTrace, DebugDiag, WinDbg, Fiddler
Strong experience with code-level profiling and optimization techniques
Hands-on experience with database performance tuning: MS SQL, MongoDB (query optimization, indexing, execution plans)
Proven ability to: Analyze and optimize code for quality, efficiency, and performance, Diagnose complex performance issues in distributed systems
Solid understanding of: Microservices and distributed system design, API performance and service interactions
Experience with observability and performance monitoring tools, such as: AppDynamics, OpenTelemetry, DBA Dash, Datadog, Prometheus, Grafana
Experience working with engineering workflows and tracking systems such as Jira
Demonstrated ability to integrate AI tools to optimize/redesign workflows and drive measurable impact
Strong collaboration and communication skills, with the ability to influence technical decisions

Nice To Haves

Experience with performance testing tools (e.g., JMeter, Gatling, k6, LoadRunner)
Familiarity with CI/CD pipelines and integrating performance validation into workflows
Experience with containerization and orchestration (Docker, Kubernetes)
Experience with advanced profiling techniques (e.g., flame graphs, heap analysis, thread dumps)
Background in cloud cost optimization and efficiency engineering
Experience with non-functional requirement (NFR) gathering and performance test planning

Responsibilities

Profile, analyze, and optimize application code to improve: Execution efficiency, CPU, memory, and I/O utilization, Latency and throughput
Conduct deep-dive investigations into performance issues using tools such as: SQL Profiler, dotTrace, DebugDiag, WinDbg, Fiddler, and observability platforms
Identify and resolve performance bottlenecks at the code, database, and system level, leveraging profiling data, logs, and telemetry
Analyze and optimize: C# / ASP.NET application performance (threading, async patterns, memory usage, GC behavior), Database queries and execution plans (MS SQL, MongoDB), Network calls and API behavior
Collaborate with developers and architects to: Embed performance considerations into system design, Influence architectural decisions for scalability and efficiency, Drive performance-focused code reviews
Optimize enterprise SaaS applications across: Multi-tier web architectures, Microservices-based distributed systems
Design and execute capacity and scalability experiments to guide system sizing and cost optimization
Build and enhance tools to monitor, analyze, and visualize performance metrics in cloud environments
Analyze performance data and provide clear, actionable recommendations to engineering and product stakeholders
Leverage AI tools to automate analysis, optimize workflows, and improve engineering productivity
Contribute to and lead performance engineering best practices across teams